Sutures fabricated from polypropylene homopolymers and copolymers are from polymer blends containing polypropylene are disclosed in, among others, U.S. Pat. Nos. 3,630,205, 4,621,638 and 4,911,165 (sutures obtained by the melt extrusion of isotactic polypropylene), U.S. Pat. Nos. 4,520,822 and 4,620,542 (sutures made from ethylene-propylene copolymers) and U.S. Pat. No. 4,557,264 (sutures made from blends of polypropylene and linear low density polyethylene).
Medical devices, including sutures, fabricated from syndiotactic polypropylene and/or a blend of syndiotactic polypropylene and at least one other thermoplastic polymer are disclosed in U.S. Pat. No. 5,269,807.
Atactic isotactic stereoblock alpha-olefin polymers, including polypropylene, are disclosed in Oscillating Stereocontrol: A Strategy for the Synthesis of Thermoplastic Elastomeric Polypropylene Science, Coates and Waymouth, Vol. 267, Jan. 13, 1995. Such stereoblock alpha-alpha-olefin polymers are reported therein to be thermoplastic elastomeric alpha-olefins.
As good as commercially available polypropylene sutures are today, it would be advantageous to provide a suture, which exhibits even greater flexibility and handling characteristics then commercially available polypropylene sutures while maintaining other desired characteristics, such as tensile strength, knot strength, and knot retention.